Patent GB-1129439-A (GB)
Title: Improvements in printing plate saddle
IPC: B41F27/10
Filed: 1967-02-23
Abstract: 1,129,439. Printing plate saddle. NATIONAL ELECTROTYPE CO. Inc. 23 Feb., 1967 [2 March, 1966], No. 8619/67. Heading B6C. A printing plate saddle comprises a body member, which has curved outer and under surfaces and is adapted to be locked on to the surface of a printing cylinder; adjustable plate clamping members connected to at least one of the opposite ends of the body member, i.e. those ends extending parallel to the longitudinal axis of the cylinder; clamping surfaces on the clamp - ing members facing away from the body member to receive bent ends of printing plates; and adjustable mounting means for connecting the clamping members to an end of the body member for movement between a first position where a plate is loosely received over the clamping surfaces and a second position where the plate is locked under tension on to the saddle. Fig. 3 is a partial plan view of the undersurface of a saddle comprised generally of a body member 1 and a clamping member 3 attached to an end (2) of the body member; the saddle is curved to fit the curved surface of a printing cylinder (5) and is adapted to receive a plate P on its outer surface, tension hooks (7) on the cylinder interlocking with scarf notches 6 on the saddle (Fig. 1, not shown). The end (2) of the body member 1 is preferably formed of separate pieces 2a attached by screws 4; the clamping member 3 is adjustably connected to end (2) of the body member by support pins 8 in aligned holes 10 and adjusting screws 9 abutting against the end member 2a; the outward movement of the clamping member 3 is restricted by locking members 13 which comprise screws with enlarged heads co-operating with shoulders formed in corresponding holes in the member 3. Fig. 4 is a cross-section on the line 4-4 of Fig. 3, and shows the outer surfaces 17, 18 of members 2a, 3 curved to form an extension of the curved surfaces of body member 1; likewise, the inner surfaces 19, 20 are curved to fit the cylinder. Each of the clamping members has a portion 21 bevelled inwardly for a distance sufficient to receive the bent end of a plate P, the portion 21 terminating in a ledge 22 and a rear perpendicular portion 23 in which the various holes are bored. In use, the plate P is draped over a saddle, and the clamping members 3 are moved outwardly on the support pins 8 by means of individual adjustment of screws 9 to tension the plate. A further embodiment of the invention involves constructing the saddle to receive either full-page, “-page or ¢-page plates wherein the body member is provided with a dovetailed slot 33 extending the entire length of the saddle in the middle, one clamping member 34 being used at each end (Fig. 10); one bent-over end of a plate P<SP>1</SP> being inserted in the slot 33, the other end being bent over clamping member 34 and tensioned according to the invention above. In the case of a single full-page plate, a dovetailed bar can be inserted in the slot 33 separately (Fig. 12, not shown). A further alternative to the dovetail slot are two angled slots which eliminate the necessity for the bar (Fig. 11, not shown). Registration marks for multi-colour plates may be provided on the saddle (Fig. 2, not shown).